Code:

/**
 * @param {number[][]} matrix
 * @return {void} Do not return anything, modify matrix in-place instead.
 */
var rotate = function(matrix) {
    const n = matrix.length

    for (let i = 0; i < Math.floor(n / 2); i++) {
        for (let j = 0; j < Math.floor((n + 1) / 2); j++) {
            const temp = matrix[i][j]

            matrix[i][j] = matrix[n - 1 - j][i]
            matrix[n - 1 - j][i] = matrix[n - 1 - i][n - 1 - j]
            matrix[n - 1 - i][n - 1 - j] = matrix[j][n - 1 - i]
            matrix[j][n - 1 - i] = temp
        }
    }

    return matrix
};

console.log(rotate([[1,2,3],[4,5,6],[7,8,9]]))
console.log(rotate([[5,1,9,11],[2,4,8,10],[13,3,6,7],[15,14,12,16]]))